When 4140 PMP is attached to sil24, NCQ commands to fan out port 1 and 2 (0 based) often stall if commands are in progress to other ports. I've tried a number of things but can't tell what's going on. It never happens w/ ahci and reportedly sata_mv which can issue NCQ commands to multiple devices simultaneously like sil24 does. Disable NCQ for devices behind 4140 PMP for the time being. Signed-off-by: Tejun Heo <htejun@xxxxxxxxx> Cc: Mark Lord <liml@xxxxxx> --- drivers/ata/sata_sil24.c | 11 +++++++++++ 1 files changed, 11 insertions(+), 0 deletions(-) diff --git a/drivers/ata/sata_sil24.c b/drivers/ata/sata_sil24.c index 27a1101..8ee6b5b 100644 --- a/drivers/ata/sata_sil24.c +++ b/drivers/ata/sata_sil24.c @@ -899,14 +899,25 @@ static bool sil24_qc_fill_rtf(struct ata_queued_cmd *qc) static void sil24_pmp_attach(struct ata_port *ap) { + u32 *gscr = ap->link.device->gscr; + sil24_config_pmp(ap, 1); sil24_init_port(ap); + + if (sata_pmp_gscr_vendor(gscr) == 0x11ab && + sata_pmp_gscr_devid(gscr) == 0x4140) { + ata_port_printk(ap, KERN_INFO, + "disabling NCQ support due to sil24-mv4140 quirk\n"); + ap->flags &= ~ATA_FLAG_NCQ; + } } static void sil24_pmp_detach(struct ata_port *ap) { sil24_init_port(ap); sil24_config_pmp(ap, 0); + + ap->flags |= ATA_FLAG_NCQ; } static int sil24_pmp_hardreset(struct ata_link *link, unsigned int *class, -- 1.5.2.4 -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html